Maja Jaakson from the University of Amsterdam visits the Wittgenstein Archives in the period 8-18 September 2012. In this context, she gives a paper:
Monday, 17 September, 13.15-14.00, Room 210, Sydnesplassen 12/13: Whats a Theory to Do? On Classicality with the Purpose of Capturing
What do we want in, and from, a formal theory of truth? In his What Theories of Truth Should Be Like (but Cannot Be), Hannes Leitgeb presents eight desiderata for such theories, including that the theory have a classical outer logic. Leitgeb makes classicality a desideratum because he thinks we reason classically in mathematics, science, and philosophy; and this suggests an ideal theory of truth will capture our inferential practices involving the concept of truth in those disciplines. Thus, for Leitgeb, we go classical with the purpose of capturing. In the present paper, I argue that Leitgebs reasons for preserving classical logic are, at the very least, equally good reasons for accepting STTT: a three-valued logic with a non-transitive consequence relation. I also argue that Leitgebs criteria present us with a problem when it comes to deciding just which largely classical theory of truth is the correct one.